TW201908508A - Method of depositing a barrier layer on a metal surface - Google Patents

Abstract

Methods of enhancing selective deposition are described. In some embodiments, a blocking layer is deposited on a metal surface before deposition of a dielectric. In some embodiments, a metal surface is functionalized to enhance or decrease its reactivity.

Description

Method for depositing barrier layer on metal surface

The examples disclosed in this case relate to a method for depositing a barrier layer on a metal surface. More specifically, embodiments disclosed herein relate to a method of depositing a barrier layer on a metal surface to help deposit silicon nitride only on a dielectric surface.

The semiconductor industry faces many challenges in pursuing component miniaturization, which involves the rapid downsizing of nanometer-level features. Such problems include the introduction of complex manufacturing steps, such as multiple lithographic steps, and the integration of high-performance materials. In order to maintain the pace of component miniaturization, selective deposition has emerged as it has the potential to remove costly lithographic steps by simplifying integration schemes.

The selective deposition of materials can be accomplished in a variety of ways. Chemical precursors can selectively react with one surface (relative to the other) (metal or dielectric). Process parameters such as pressure, substrate temperature, precursor partial pressure, and / or gas flow can be adjusted to regulate the chemical dynamics of specific surface reactions. Another possible solution involves surface preparation, which can be used to activate or deactivate the surface to which the introduced film deposition precursor is directed.

There is a continuing need in the art for improved deposition selectivity.

This case discloses one or more embodiments regarding a method for selectively depositing a barrier layer. The method includes exposing a substrate having a metal surface and a dielectric surface to a silane, and selectively forming a barrier layer on the metal surface. The silane includes at least one compound, the general formula of the compound is SiH ₃ R, where R is An alkyl, perfluorinated alkyl, alkenyl, or alkynyl group selected from C4 to C20.

Additional embodiments disclosed herein relate to a method for selectively depositing a barrier layer. The method includes exposing a substrate having a metal surface and a dielectric surface to an alkyne and a nitrogen reactant, and selectively forming a barrier layer on the metal surface, the nitrogen reactant including an azide or a nitrile oxide.

A further embodiment of the present disclosure relates to a method for selectively depositing a barrier layer. The method includes exposing a substrate having a metal surface and a dielectric surface to an epoxide, and selectively forming a barrier layer on the metal surface.

The embodiments disclosed in this case provide various methods for depositing a barrier layer on a metal surface. The examples disclosed in this case verify multiple methods for depositing barrier layers that can be used separately or in concert.

The embodiments disclosed in this case provide a method for favorably depositing a dielectric material (such as SiN) on a dielectric surface, which is achieved by blocking a metal surface via a barrier layer deposited on the metal surface Deposition of electrical materials.

The "substrate surface" as used herein refers to a portion of a surface of a material formed on a substrate or any portion of a substrate on which film processing is performed. For example, the surface of a substrate on which processing can be performed includes materials such as: silicon, silicon oxide, silicon nitride, doped silicon, germanium, gallium arsenide, glass, sapphire, and any other materials such as metal, metal Nitride, metal alloy, and other conductive materials, depending on the application. The substrate includes, but is not limited to, a semiconductor wafer. The substrate may be exposed to a pre-processing process to grind, etch, reduce, oxidize, oxidize, anneal, UV cure, electron beam cure, and / or bake the substrate surface. In addition to performing film processing directly on the surface of the substrate itself, in the disclosure of this case, any of the disclosed film processing steps can also be performed on the lower layer, which is formed on the substrate, which will be disclosed in more detail below. And it is desirable that the term "substrate surface" includes such an underlying layer as the context indicates. Thus, for example, when a film / layer or a portion of a film / layer has been deposited on a substrate surface, the exposed surface of the newly deposited film / layer becomes the substrate surface. The substrate may have various sizes, such as a wafer having a diameter of 200 mm or 300 mm, and a rectangular or square plate. In some embodiments, the substrate comprises a rigid discrete material.

As used herein, "atomic layer deposition" or "cyclic deposition" refers to a process that includes sequentially exposing two or more reactive compounds to deposit a material layer on a substrate surface. As used in this specification and the scope of the accompanying patent applications, the terms "reactive compound", "reactive gas", "reactive species", "precursor", "processing gas", and similar terms are used interchangeably It means that a substance has a species capable of reacting with a substrate surface or a material on the substrate surface in a surface reaction such as chemical adsorption, oxidation, reduction, cycloaddition. The substrate (or a portion of the substrate) is sequentially exposed to the two or more reactive compounds, which are introduced into a reaction area of the processing chamber.

The embodiments disclosed in this case advantageously provide a method for surface pretreatment such as selective blocking of metal surfaces (including but not limited to copper, cobalt, tungsten, tantalum, tantalum nitride, tantalum oxide, titanium, oxide Titanium, titanium nitride, ruthenium, ruthenium oxide, iridium, etc.). Some embodiments advantageously provide a method for selectively growing dielectric materials, such as SiO ₂ , SiN, SiCON, SiCO, and the like, on a dielectric surface. Some embodiments advantageously provide a method for selectively blocking surface deposition using an epoxide surface reaction.

In some embodiments, the metal silicide is selectively formed on the metal surface rather than on the dielectric surface. As used in this specification and the scope of the accompanying patent application, the term "selectivity ... is better than" or similar means that the material is deposited to a greater extent on the stated surface than on another surface. In some embodiments, "selectivity" means that the material is formed on the selective surface at a rate greater than or equal to about 10 times, 15 times, 20 times, the rate of formation on a non-selected surface, 25 times, 30 times, 35 times, 40 times, 45 times, or 50 times. In some embodiments, trihydridosilane (RSiH ₃ , where R = C4-C20) containing a long alkyl chain is used as a blocking molecule, and is in solution or gas phase with metal surfaces (including but not limited to Cu, Co , W, and TiN) reactions. In some embodiments, the metal surface is cleaned before reacting with the blocking molecules. Through silane head groups, organic silanes react more selectively with metal surfaces than with dielectric surfaces (such as SiO ₂ ). The organic part of the silane acts as a hydrophobic protective layer, while blocking the growth of subsequent dielectric layers (such as SiN) on the metal, to achieve selective deposition of a dielectric on the dielectric surface.

One or more embodiments disclosed herein relate to a method for selectively depositing a barrier layer on a metal surface of a substrate having a metal surface and a dielectric surface. The method includes exposing the substrate to a silane, the silane comprising at least one compound, the general formula of which is SiH ₃ R, wherein R is an alkyl group, a perfluorinated alkyl group, an alkenyl group, or an alkyne group selected from C4 to C20 Group. As used in this manner, the letter "C" followed by a numerical value (eg, "C4") means that the substituent includes a specified number of carbon atoms (eg, C4 includes four carbon atoms). In some embodiments, the substituent may be a linear group (such as n-butyl), a branched group (such as a third butyl group), or a cyclic group (such as cyclohexyl).

The dielectric surface of the substrate may include any suitable dielectric material. Suitable dielectric materials include, but are not limited to, oxides (such as silicon oxide) and high-k dielectrics. In some embodiments, the dielectric surface consists essentially of silicon oxide. As used in this manner, the term "consisting essentially of" means that the surface is, on an area basis, the material having greater than or equal to about 95%, 98%, or 99%.

The metal surface of the substrate may include any suitable metal material. Suitable metal materials include, but are not limited to, metals, metal nitrides, metal alloys, and other conductive materials. In some embodiments, the metal surface includes one or more of cobalt, tungsten, or titanium nitride. In some embodiments, the metal surface consists essentially of cobalt. In some embodiments, the metal surface consists essentially of tungsten. In some embodiments, the metal surface consists essentially of titanium nitride.

The silane exposed to the substrate may include any suitable trihydrosilane. In some embodiments, the silane includes at least one compound having a general formula SiH ₃ R, wherein R is an alkyl group, a perfluorinated alkyl group, an alkenyl group, or an alkynyl group selected from C4 to C20. In some embodiments, the C4 to C20 alkyl group consists essentially of a silicon-carbon bond, multiple carbon-carbon single bonds, and multiple carbon-hydrogen bonds. In some embodiments, the C4 to C20 perfluorinated alkyl group consists of one silicon-carbon bond, multiple carbon-carbon single bonds, and multiple carbon-fluorine bonds. In some embodiments, the C4 to C20 alkenyl group consists of one silicon-carbon bond, multiple carbon-carbon single bonds, at least one carbon-carbon double bond, and multiple carbon-hydrogen bonds. In some embodiments, the C4 to C20 alkynyl group consists essentially of a silicon-carbon bond, multiple carbon-carbon single bonds, at least one carbon-carbon triple bond, and multiple carbon-hydrogen bonds. In some embodiments, the C4 to C20 group includes one or more halogen atoms and / or a hydrophobic moiety.

In some embodiments, the silane includes a C4 to C20 alkyl group. In some embodiments, the silane includes dodecylsilane (C ₁₂ H ₂₅ SiH ₃ ). In some embodiments, the silane consists essentially of dodecylsilane.

In some embodiments, the silane groups are crosslinked to each other after deposition. In some embodiments, the barrier layer is substantially free of cross-linking between silane groups. As used in this regard, the term "substantially free of ..." means that there is less than or equal to about 5%, 2%, or 1% of crosslinks on a surface area basis.

In some embodiments, the substrate is cleaned before the substrate is exposed to silane. In some embodiments, only the metal surface of the substrate is cleaned before the substrate is exposed to silane. In some embodiments, the metal surface of the substrate or the substrate is cleaned with a hydrogen plasma. In some embodiments, the hydrogen plasma is a conductive coupling plasma (CCP). In some embodiments, the hydrogen plasma is an inductively coupled plasma (ICP). In some embodiments, the hydrogen plasma includes a H ₂ plasma.

In some embodiments, after the barrier layer is deposited, a dielectric layer is selectively deposited on the dielectric surface. In some embodiments, the dielectric layer includes silicon nitride. Deposition of silicon nitride can be performed by any suitable process. A suitable process may include exposing the substrate to silicon halide and ammonia. Suitable silicon halides include, but are not limited to, dichlorosilane (DCS), trichlorosilane (TCS), tetrachlorosilane (SiCl ₄ ), tetrabromosilane (SiBr ₄ ), tetraiodosilane (SiI ₄ ), and six Chloroethylsilane (HCDS).

In some embodiments, the substrate is repeatedly exposed to the silane after the dielectric layer is deposited to regenerate the barrier layer. In some embodiments, the dielectric layer is deposited again after the barrier layer is regenerated. In some embodiments, the substrate is repeatedly exposed to silane and a silicon nitride layer is deposited until the silicon nitride layer has reached a predetermined thickness.

After a certain number of deposition cycles, or after the film thickness is formed, the surface barrier chemical conditions may be exposed once or repeatedly, or the barrier layer may be regenerated. In some embodiments, the silicon nitride layer is deposited to a thickness ranging from about 10 Å to about 50 Å, or from about 12 Å to about 35 Å, or from about 15 Å to about 20 Å before the barrier layer is regenerated. In some embodiments, the substrate is repeatedly exposed to the silane and silicon nitride is deposited until the silicon nitride layer has a thickness greater than or equal to 50 Å, 75 Å, 100 Å, or 150 Å. example

Clean the metal surface with a 100 watt hydrogen plasma for 2 to 10 minutes to reduce the native oxide concentration. Silane was deposited at a substrate temperature of 200 ° C. Initially, the formation of metal silicide was investigated by water contact angle (WCA) measurement. A higher contact angle indicates a hydrophobic surface (ie, silicide formation). WCA indicates that SiO _{2 is} not blocked by dodecylsilane (DDS, R = C12), and the metal surface (ie Co, W, and TiN) is blocked. Hydrogen plasma treatment for surface cleaning facilitates metal silicide formation.

Thermal and chemical stability test results indicate that the DDS barrier on metals is stable up to 200 ° C for W and TiN, and is stable up to 330 ° C on Co. DDS self-assembled monolayer (SAM) can withstand silicon halide (dichlorosilane (DCS), trichlorosilane (TCS), tetrachlorosilane (SiCl ₄ ), tetrabromosilane (SiBr ₄ ), tetraiodosilane (SiI ₄ )) And NH ₃ , both of which are used for SiN ALD.

WCA studies of SiN deposited on DDS SAM with different thicknesses have shown that when SAM is regenerated after 15-20Å SiN growth, the minimum thickness of up to about 50Å on Co, W, and TiN surfaces can achieve selectivity. By repeating the number of regeneration cycles between SiN formations, the selectivity can be extended. It was observed that DDS-treated substrates had almost no SiN growth (the SiN was oxidized to SiO ₂ due to air exposure), whereas substrates not treated with DDS had SiN growth of about 40-50 Å.

In some embodiments, a substituted azide or nitrile oxide and an alkyne react in the presence of a copper surface to form a barrier layer. This reaction forms a surface-bonded species that can have the potential to make the newly functionalized copper surface inert, or to promote reactivity toward the introduced film deposition precursor. For example, an azide or nitrile oxide reacts with an alkyne in the presence of copper metal to form a triazole or isooxazole (formed in the case of an azide or nitrile oxide, respectively) ). In some embodiments, trimethylsilyl azide and trimethylsilyl acetylene react in the presence of a copper metal surface to form the resulting surface-bonded triazole. In some embodiments, the substituted azide and alkyne precursors are sequentially introduced to the substrate in the gas phase.

In some embodiments, a substituted azide or nitrile oxide and a substituted alkyne are reacted in the presence of a metal surface. The number N of reactive substituents on each molecule (azide, nitrile oxide, and alkyne) may be in the range of 1 to 4 reactive groups. In some embodiments, the number of reactive groups is greater than one.

Referring to FIG. 1, a series of general structures are shown for possible numbers or reactive groups of azides and alkynes. The wavy lines that hold the groups together can be any molecular chain that holds reactive groups together, such reactive groups being carbon-based, silicon-based, or even similar to boron, phosphorus, nitrogen, oxygen, and sulfur And other elements.

Without being limited by theory, when these monomers are in the presence of a metal surface, it is believed that these parts will undergo a cyclization reaction, and a polymer network is formed on the metal surface (not on the dielectric surface), as shown in Figure 2 Instructions. It is believed that the bonding of the polymer network to the metal surface occurs through the interaction of the nitrogen substituents on the polymer surface and the π electrons of the heterocycle with the metal surface.

FIG. 3 shows a general process flow for implementing selective deposition according to some embodiments of the disclosure. The process begins by passing acetylide-based (eg, alkyne) and azide-based monomers through a solution phase, neat, or gas phase process at a temperature in the range of about 20 ° C to about 600 ° C Lead to the substrate. In some embodiments, the metal surface is a pure metal surface without any oxide on the surface. After the monomers were introduced, the polymer network began to form on the metal surface through metal-catalyzed triazole formation. After the metal-catalyzed polymerization is completed, the unreacted monomers can be removed by washing the surfaces with a solvent (if performed in a solution phase) or by flushing with an inert gas inside the reactor. A film that nucleates only on the dielectric can then be deposited.

After the process flow is completed, the polymer layer can be removed using a selective etching process. Oxygen-based and fluorine-based etching is known to etch carbon-based films, similar to the barrier layer deposited here. Figure 4 shows an example of polymer removal through an oxygen-based remote plasma. In this example, the polymer is removed through an oxygen-based remote plasma etch, which removes the polymer but oxidizes the metal surface. In order to restore the original metal surface, the metal oxide can be reduced back to the metal. In some embodiments, the reduction includes exposure to H ₂ and NH ₃ plasma and / or H ₂ and NH ₃ thermal annealing.

In some embodiments, some deposition of the film can occur on the barrier layer, which may cause defects (as indicated by the nodules in FIG. 5). In one or more embodiments, the polymer is removed along with the defects, and the polymerization reaction restarts again, and the selective growth continues.

One or more embodiments disclosed herein relate to a method for selectively depositing a barrier layer on a metal surface of a substrate having a metal surface and a dielectric surface. The method includes exposing the substrate to an alkyne and a nitrogen reactant, and selectively forming a barrier layer on a metal surface, the nitrogen reactant including an azide or a nitrile oxide.

In some embodiments, the metal surface includes copper. In some embodiments, the metal surface consists essentially of copper.

In some embodiments, the alkyne and nitrogen reactants are simultaneously exposed to the substrate. In some embodiments, the exposing is performed by exposing the solution phase of the solution through the substrate, the solution including both alkyne and nitrogen reactants. In some embodiments, the exposing is performed through a gas phase exposure of a gas through the substrate, the gas including both alkynes and nitrogen reactants.

In some embodiments, the alkyne and nitrogen reactants are sequentially exposed to the substrate. In some embodiments, the alkyne is first exposed to the substrate. In some embodiments, the nitrogen reactant is first exposed to the substrate. In some embodiments, the exposing is performed by exposing the solution phase of the solution through the substrate, the solution including an alkyne or nitrogen reactant. In some embodiments, the exposing is performed through a gas phase exposure of a gas through the substrate, the gas including an alkyne or a nitrogen reactant. In some embodiments, one exposure is in the solution phase and the other exposure is in the gas phase. In some embodiments, the substrate is washed (gas phase) or cleaned (solution phase) to remove the previous reactant, and then exposed to another reactant.

In some embodiments, the alkyne includes two or more alkyne moieties. In some embodiments, the alkyne includes two, or three, or four, or more alkyne moieties. In some embodiments, the alkyne includes at least one compound, the general formula of which is SiR ₄ , wherein each R is independently selected from C1 to C18 alkyl, aryl, or alkynyl groups, provided that at least one R Is alkynyl.

In some embodiments, the alkyne includes one or more of the following compounds: Wherein R is independently selected from a C1 to C18 alkyl or aryl group.

In some embodiments, the nitrogen reactant includes an azide. In some embodiments, the nitrogen reactant consists essentially of an azide. As used in this manner, the term "consisting essentially of azide" means that the reactive component (eg, excluding inert components) of the nitrogen reactant is greater than or equal to about 95%, 98%, or 99% azide. In some embodiments, the nitrogen reactant includes a nitrile oxide. In some embodiments, the nitrogen reactant consists essentially of a nitrile oxide. As used in this manner, the term "consisting essentially of a nitrile oxide" means that the reactive component (eg, excluding inert components) of the nitrogen reactant is greater than or equal to about 95%, 98%, or 99% nitrile oxide. In some embodiments, the nitrogen reactant does not substantially include a nitrile oxide. As used in this manner, the term "substantially excludes nitrile oxide" means that the nitrogen reactant has a nitrile oxide of less than or equal to about 5%, 2%, or 1% on a molecular basis.

In some embodiments, the azide includes two or more azide moieties. In some embodiments, the azide includes two, or three, or four, or more azide moieties. In some embodiments, the azide includes at least one compound having a general formula of SiR ₄ , wherein each R is independently selected from C1 to C18 alkyl, aryl, or azide groups, provided that at least One R is an azide.

In some embodiments, the azide includes one or more of the following compounds: Wherein R is independently selected from a C1 to C18 alkyl or aryl group.

In some embodiments, the substrate is cleaned before the substrate is exposed to an alkyne or nitrogen reactant. In some embodiments, only the metal surface of the substrate is cleaned before the substrate is exposed to an alkyne or nitrogen reactant. In some embodiments, the metal surface of the substrate or the substrate is cleaned with a hydrogen plasma. In some embodiments, the hydrogen plasma is a conductive coupling plasma (CCP). In some embodiments, the hydrogen plasma is an inductively coupled plasma (ICP). In some embodiments, the hydrogen plasma includes a H ₂ plasma.

In some embodiments, the dielectric layer is selectively deposited on the dielectric surface after the barrier layer is deposited. In some embodiments, the dielectric layer includes silicon nitride. Deposition of silicon nitride can be performed by any suitable process. A suitable process may include exposing the substrate to silicon halide and ammonia. Suitable silicon halides include, but are not limited to, dichlorosilane (DCS), trichlorosilane (TCS), tetrachlorosilane (SiCl ₄ ), tetrabromosilane (SiBr ₄ ), tetraiodosilane (SiI ₄ ), and six Chloroethylsilane (HCDS).

In some embodiments, the barrier layer is removed from the substrate. The barrier layer can be removed by any suitable selective etching process. Suitable selective etching processes include, but are not limited to, the use of oxygen plasma and fluorine plasma. In some embodiments, when the barrier layer is removed using an oxygen plasma, a metal oxide layer is formed on the metal surface. In some embodiments, the metal oxide formed on the metal surface is removed by using a reduction process. Suitable reduction processes include, but are not limited to, using a plasma including hydrogen or ammonia and thermal annealing including hydrogen or ammonia. In some embodiments, the oxygen plasma, fluorine plasma, hydrogen plasma, and ammonia plasma can be generated remotely or internally independently, and these plasmas can be conductively coupled or inductively coupled.

In some embodiments, after the silicon nitride layer is deposited, the barrier layer is removed by sequentially exposing the substrate to an oxygen plasma and a hydrogen plasma, and the substrate is exposed to alkyne and nitrogen reactants to selectively block the metal surface. A silicon nitride film is selectively deposited on the dielectric surface. The removal of the barrier layer, the exposure of the substrate, and the deposition of the silicon nitride film may be repeated until a silicon nitride film of a predetermined thickness is formed.

In some embodiments, the cobalt surface may have enhanced surface reactivity or render it inert. In some embodiments, cobalt can participate in catalysis in the presence of an epoxide to form a new functionalized surface. This newly formed surface is available for further processing.

One or more embodiments disclosed herein relate to a method for selectively depositing a barrier layer on a metal surface of a substrate having a metal surface and a dielectric surface. The method includes exposing the substrate to an epoxide to selectively form a barrier layer on a metal surface. In some embodiments, the metal surface includes cobalt. In some embodiments, the metal surface consists essentially of cobalt.

In some embodiments, the exposing is performed by exposing the solution phase of the solution including the epoxide through the substrate. In some embodiments, the exposing is performed through a substrate to a gas phase exposure of a gas including an epoxide.

In some embodiments, the epoxide includes two or more epoxide moieties. In some embodiments, the epoxide is substituted. In some embodiments, the epoxide includes two, or three, or four, or more epoxide moieties. In some embodiments, the epoxide includes one or more of the following compounds: Wherein R is independently selected from a C1 to C4 alkyl group.

In some embodiments, the epoxide includes two or more epoxide moieties that each react with a substrate surface. In some embodiments, the epoxide includes two or more epoxide moieties, only one of which reacts with a substrate surface.

In some embodiments, the substrate is cleaned before the substrate is exposed to an epoxide. In some embodiments, only the metal surface of the substrate is cleaned before the substrate is exposed to the epoxide. In some embodiments, the metal surface of the substrate or the substrate is cleaned with a hydrogen plasma. In some embodiments, the hydrogen plasma is a conductive coupling plasma (CCP). In some embodiments, the hydrogen plasma is an inductively coupled plasma (ICP). In some embodiments, the hydrogen plasma includes a H ₂ plasma.

In some embodiments, the dielectric layer is selectively deposited on the dielectric surface after the barrier layer is deposited. In some embodiments, the dielectric layer includes silicon nitride. Deposition of silicon nitride can be performed by any suitable process. A suitable process may include exposing the substrate to silicon halide and ammonia. Suitable silicon halides include, but are not limited to, dichlorosilane (DCS), trichlorosilane (TCS), tetrachlorosilane (SiCl ₄ ), tetrabromosilane (SiBr ₄ ), tetraiodosilane (SiI ₄ ), and six Chloroethylsilane (HCDS).

In some embodiments, the barrier layer is removed from the substrate. The barrier layer can be removed by any suitable selective etching process. Suitable selective etching processes include, but are not limited to, the use of oxygen plasma and fluorine plasma. In some embodiments, when the barrier layer is removed using an oxygen plasma, a metal oxide layer is formed on the metal surface. In some embodiments, the metal oxide layer formed on the metal surface is removed by using a reduction process. Suitable reduction processes include, but are not limited to, using a plasma including hydrogen or ammonia and thermal annealing including hydrogen or ammonia. In some embodiments, the oxygen plasma, fluorine plasma, hydrogen plasma, and ammonia plasma can be generated remotely or internally independently, and these plasmas can be conductively coupled or inductively coupled.

Silyl halide precursors usually do not chemically adsorb on the surface of SiO ₂ because the surface Si-OH groups do not react with Si-Cl under gas-phase ALD conditions. For example, an ALD SiO ₂ film is not formed from a SiCl ₄ / H ₂ O process under normal ALD conditions. However, the inventors have found that adding a titanium precursor to an ALD scheme (SiCl ₄ / H ₂ O / TiCl ₄ / H ₂ O) can cause Ti _x Si _y O _z film formation.

Without being limited by theory, it is believed that although Si-OH does not react with Si-Cl, Ti-OH reacts with Si-Cl because Ti has a lower electronegativity than Si, and Ti-OH is more reactive than Si-OH. Si-Cl is more reactive. In some embodiments, this difference in reactivity is used to block TiN without blocking SiO ₂ .

The TiN surface oxidizes once exposed to air, and the surface will have Ti-OH groups. When RSiCl ₃ (SAM) is pulsed in the air to the exposed TiN and SiO ₂ surfaces, the Si-Cl bond will react with the surface Ti-OH instead of the Si-OH.

Some embodiments disclosed in this case relate to a method for blocking TiN, W, Cu, or Co by a trichlorosilyl hydrocarbon in the gas phase and / or solution phase. In some embodiments, TiN, W, Cu, or Co surfaces are blocked by a variety of compounds. The general formula of these compounds is SiX ₃ R, where X is halogen, and R is C1 to C18 alkyl, aryl, and alkylamine. .

One or more embodiments disclosed herein relate to a method for selectively depositing a barrier layer on a metal surface of a substrate having a metal surface and a dielectric surface. The method includes exposing a substrate to a trihalosilyl hydrocarbon to selectively form a barrier layer on a metal surface. The trihalosilyl hydrocarbon includes at least one compound, the general formula of the compound is SiX ₃ R, wherein X is halogen, and R is C1 to C18 alkyl, aryl, and alkylamino.

In some embodiments, the exposure to the trihalosilyl hydrocarbon is performed through the substrate to the solution phase of the solution including the trihalosilyl hydrocarbon. In some embodiments, the exposure to the trihalosilyl hydrocarbon is performed through the substrate to the gas phase of the gas including the trihalosilyl hydrocarbon.

In some embodiments, the trihalosilyl hydrocarbon includes one or more of the following compounds: R = Cl, Br, IR ₁ = tBu, Me, Et, iPr, hydrocarbons from C3 to C18, NMe ₂ , Net ₂ , phenyl, benzyl

In some embodiments, R ₁ is any C1-C18 alkyl, aryl, alkylamino, or benzyl.

In some embodiments, the trihalosilyl hydrocarbon includes at least one compound, the general formula of the compound is SiX ₃ R, wherein R is a C1 to C18 alkyl group, an aryl group, and an alkylamine group. As used herein, "alkylamino" means an amine group having an alkyl substituent. In other words, the alkylamino substituent has the general formula of -NR ₂ where each R is independently H, C1 to C6 alkyl, or aryl. For example, -N (CH ₃ ) ₂ and -N (CH ₂ CH ₃ ) ₂ .

In some embodiments, the substrate is exposed to air before the substrate is exposed to a trihalosilyl hydrocarbon. In some embodiments, only the metal surface of the substrate is exposed to the air before the substrate is exposed to the trihalosilyl hydrocarbon. example

Blocking the TiN surface by ODTS (octadecyltrichlorosilane)

ODTS was dissolved in toluene, and the sample was immersed in the solution at room temperature for a set period of time. After soaking, the samples were washed with toluene and dried with nitrogen. SAM formation was monitored by measuring water contact angle (WCA). During the 1 second immersion, the formation of SAM was filled on TiN (but not on SiO ₂ ). As the immersion time increased, the WCA on TiN remained constant but the WCA on SiO ₂ increased.

Low-temperature ALD SiON was deposited on a SAM-treated substrate to evaluate selective dielectric deposition. The substrate was maintained at 200 ° C, and alternating pulses of hexachloroethanesilane (HCDSO) and NH ₃ were performed. The film thickness of SiON is measured by an ellipsometry. 5-fold selectivity was observed after 150 cycles. As the number of cycles increases, the selectivity decreases.

Blocking the TiN surface by OTS (octyl propyl silane)

OTS is dissolved in toluene, and the sample is immersed in the solution at room temperature for a set period of time. After soaking, the samples were washed with toluene and dried with nitrogen. SAM formation was monitored by measuring water contact angle (WCA). WCA changes show a similar trend to ODTS experiments.

The thermal stability of SAM deposited on the surface of various substrates was evaluated by WCA measurement. OTS SAM is deposited in a solution phase and a gas phase. The samples with SAM deposition were annealed at a temperature from 200 ° C to 350 ° C for 1 hour, and the WCA was measured before and after annealing. It was found that the SAMs on TiN and W were stable up to 250 ° C, but deteriorated beyond this temperature. In contrast, SAM on SiO ₂ is stable to more than 350 ° C. Compared with the solution phase, vapor phase SAM deposition gives more flexibility to achieve higher WCA changes between TiN and SiO ₂ .

The chemical stability of SAM was evaluated by annealing an SAM-deposited sample at 200 ° C for one hour in the precursors (HCDSO and NH ₃ ) used in SiON deposition. Although SAM is stable at 200 ° C in the ALD precursor, there is still some degradation.

One or more embodiments of the method use an atomic layer deposition (ALD) process to provide a barrier layer. In a time-domain ALD process, the exposure to each reactive compound is separated by a time delay to allow each compound to attach and / or react on the substrate surface, and then rinse these from the processing chamber. Compound. The reactive gases are prevented from being mixed by flushing the reactive gases from the processing chamber between subsequent exposures.

During the spatial ALD process, reactive gases flow into different processing areas within the processing chamber. The different processing regions are separated from adjacent processing regions so that the reactive gases do not mix. The substrate can be moved between the processing regions to separately expose the substrate to a processing gas. During substrate movement, different portions of the substrate surface (or materials on the substrate surface) are exposed to the two or more reactive compounds such that any given point on the substrate is substantially not simultaneously exposed to more than one reactive compound. As understood by those skilled in the art, it is possible that a small portion of the substrate may be exposed to multiple reactive gases simultaneously due to gas diffusion within the processing chamber, and the simultaneous exposure is not intentional unless otherwise specified.

In one aspect of the time-domain ALD process, the first reactive gas (ie, the first precursor or compound A) is pulsed to the reaction zone, followed by a first time delay. Next, a second precursor or compound B is pulsed into the reaction zone, followed by a second delay. During each time delay, a flushing gas, such as argon, is introduced into the processing chamber to flush the reaction zone, or otherwise remove any remaining reactive compounds or reaction products or by-products from the reaction zone. Alternatively, the flushing gas may flow continuously throughout the deposition process so that only the flushing gas flows during the time delay between pulses of the reactive compound. The reactive compounds are alternately pulsed until a predetermined film or film thickness is formed on the substrate surface. In either scenario, the ALD process of pulsed compound A, flushing gas, compound B, and flushing gas is one cycle. The cycle may begin with compound A or compound B, and the respective sequences of the cycle are continued until a film with a predetermined thickness is reached.

In the embodiment of the spatial ALD process, the first reactive gas and the second reactive gas are simultaneously delivered to the reaction zone, but are separated by an inert gas curtain and / or a vacuum curtain. The air curtain may be a combination of an inert gas flow entering the processing chamber and a vacuum flow leaving the processing chamber. The substrate is moved relative to the gas delivery device such that any given point on the substrate is exposed to the first reactive gas and the second reactive gas.

"Pulse" or "dispensing" as used herein refers to the amount of source gas introduced intermittently or discontinuously into the processing chamber. The amount of a particular compound within each pulse can vary over time, depending on the duration of the pulse. A particular process gas may include a single compound or a mixture / combination of two or more compounds.

The duration of each pulse / dispensing is variable and can be adjusted to, for example, the volume capacity of the processing chamber and the capacity of the vacuum system coupled to the processing chamber. In addition, the dosing time of the processing gas may vary according to the following factors: the flow rate of the processing gas, the temperature of the processing gas, the type of the control valve, the type of the processing chamber used, and the component of the processing gas adsorbed on the surface of the substrate ability. The dosing time may also vary depending on the type of layer formed and the geometry of the element formed. The formulation time should be long enough to provide a volume of compound sufficient to adsorb / chemically adsorb onto the substantially entire surface of the substrate and form a processing gas component layer thereon.

Although the embodiment of the processing method described above includes only two pulses of reactive gas, it will be understood that this is merely exemplary and that additional pulses of processing gas may be used. These pulses may be repeated in whole or in part. This cycle can be repeated to form a barrier layer having a predetermined thickness. In some embodiments, the cycle is repeated to form a barrier layer having a thickness in a range of about 5 Å to about 40 Å, or in a range of about 10 Å to about 30 Å, or in a range of about 15 Å to about Within 20 Å.

Once the predetermined thickness has been reached, the method optionally includes further processing, such as bulk deposition of a dielectric film, as appropriate. In some embodiments, the further processing may be an ALD process. For example, in some embodiments, an ALD process may be performed to deposit a body of silicon nitride layer to a target thickness.

Although the disclosure in this case has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely illustrative of the principles and applications of the disclosure in this case. For those familiar with this technology, it is obvious that various modifications and changes can be made to the methods and equipment disclosed in this case, but the spirit and scope of the contents disclosed in this case cannot be deviated. Therefore, it is hoped that the contents disclosed in this case include modified forms and changed forms falling within the scope of the attached patent application and their equivalents.

no

By referring to the embodiments (some of which are shown in the description of the drawings), a more specific description of the disclosure of the present case, which is briefly summarized above, can be obtained, and the above-mentioned features of the disclosure of the present case can be understood in detail. It should be noted, however, that the drawings only illustrate typical embodiments of the disclosure in this case, so these drawings should not be considered as limiting the scope of the disclosure in this case, as the disclosure in this case allows other equivalent embodiments.

Figure 1 shows a series of general structures regarding the possible number or reactive groups used for azide and alkyne blockers according to one or more embodiments disclosed in this case;

FIG. 2 is a schematic diagram of a reaction of a monomer that generates a polymerization network on a metal surface in the presence of a metal surface and a cyclization reaction according to one or more embodiments disclosed in this case; FIG.

FIG. 3 shows a general process flow for selectively depositing a polymer barrier layer on a metal surface and selectively depositing a dielectric film on a dielectric surface according to one or more embodiments disclosed in the present case;

4 shows an example of a process for removing a polymer barrier layer by using an oxygen-based remote plasma and a hydrogen-based remote plasma according to one or more embodiments disclosed in this case; and

FIG. 5 shows a process flow for a selective deposition process according to one or more embodiments of the disclosure.

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Information on foreign deposits (please note in order of deposit country, institution, date, and number) None

Claims (20)

A method for selectively depositing a barrier layer, the method comprising: exposing a substrate having a metal surface and a dielectric surface to a silane, and selectively forming a barrier layer on the metal surface, the silane including at least one compound, The general formula of the compound is SiH ₃ R, where R is an alkyl, perfluorinated alkyl, alkenyl, or alkynyl group selected from C4 to C20. The method of claim 1, wherein the metal surface comprises cobalt, tungsten, or titanium nitride. The method of claim 1, wherein the silane comprises dodecylsilane (C ₁₂ H ₂₅ SiH ₃ ). The method of claim 1, further comprising: cleaning the metal surface with a hydrogen plasma before exposing the substrate to the silane. The method according to claim 1, further comprising: selectively depositing a silicon nitride layer on the dielectric surface. The method according to claim 5, further comprising: repeatedly exposing the substrate to a silane and depositing a silicon nitride layer until the silicon nitride layer has reached a predetermined thickness. A method for selectively depositing a barrier layer includes: exposing a substrate having a metal surface and a dielectric surface to an alkyne and a nitrogen reactant, and selectively forming a metal surface on the metal surface. A barrier layer, the nitrogen reactant comprising an azide or a nitrile oxide. The method of claim 7, wherein the metal surface comprises copper. The method according to claim 7, further comprising: cleaning the metal surface with a hydrogen plasma before exposing the substrate to the alkyne or nitrogen reactant. The method of claim 7, wherein the alkyne comprises two or more alkyne moieties. The method of claim 7, wherein the alkyne comprises at least one compound, the general formula of which is SiR ₄ , wherein each R is independently selected from C1 to C18 alkyl, aryl, or alkynyl groups, Provided that at least one R is alkynyl. The method of claim 7, wherein the azide includes two or more azide moieties. The method of claim 7, wherein the azide includes at least one compound having a general formula of SiR ₄ , wherein each R is independently selected from C1 to C18 alkyl, aryl, or azide groups Group, provided that at least one R is an azide. The method of claim 7, wherein the nitrogen reactant does not substantially include a nitrile oxide. The method according to claim 7, further comprising: selectively depositing a silicon nitride layer on the dielectric surface. The method of claim 15, further comprising: repeatedly removing the barrier layer and exposing the substrate to the alkyne and nitrogen reactants, selectively blocking the metal surface, and selectively depositing on the dielectric surface A silicon nitride film is formed to form a silicon nitride film with a predetermined thickness, wherein the barrier layer is removed from the substrate by sequentially exposing the substrate to an oxygen plasma and a hydrogen plasma. A method for selectively depositing a barrier layer includes: exposing a substrate having a metal surface and a dielectric surface to an epoxide, and selectively forming a barrier layer on the metal surface. The method of claim 17, wherein the metal surface includes cobalt. The method of claim 17, wherein the epoxide is substituted. The method of claim 17, wherein the epoxide contains more than one epoxide moiety.